The present invention relates to an image forming apparatus capable of forming an image of desired colors by using a digital equipment, such as a word processor, on an image forming sheet on which a plurality of color areas are regularly formed, and a method for forming the image.
There has been utilized an image forming apparatus, such as a transfer ribbon type printer, an ink jet printer, etc., as a printer of a word processor. When such an image forming processor driven by digital control is used in color printing, a transfer ribbon for at least three primary colors is used, or an ink jet mechanism for the three primary colors is provided, to successively print three images of the three primary colors respectively on printing paper.
According to color printing performed by the use of the image forming apparatus mentioned above, the kind and amount of the transfer ribbon or the size of the printing facility itself will become three to four times as large as those used in a monochromatic printing apparatus.
It is an object of the present invention to provide an image forming apparatus which is capable of color printing by a single printing operation, and a method of forming images.
According to a first aspect of the present invention, there is provided an image forming apparatus for use in forming a print image of desired colors on a color image forming sheet on which a plurality of color areas are regularly formed, comprising recording means for selectively changing colors of a desired part of said color areas on said color image forming sheet; and control means for producing print image data for forming a print image with a color mixture of said color areas by changing at least a part of colors of said color areas on said color image forming sheet in accordance with plotted image data showing a plotted image, and for controlling said recording means on the basis of said print image data, to thereby form a print image on said color image forming sheet.
According to a second aspect of the present invention, there is provided an image forming apparatus for use in forming a print image of desired colors on a color image forming sheet on which a plurality of color areas are regularly formed, comprising display means for displaying a plotted image; input means for designating colors for said plotted image displayed on said display means; recording means for selectively changing colors of a desired part of said color area on said color image forming sheet; and control means for controlling said recording means on the basis of color designation by said input means, and changing color in at least a part of said color area on said color image forming sheet, to thereby form a print image on said color image forming sheet with a mixture of colors of said color area.
According to a third aspect of the present invention, there is provided an image forming apparatus for use in forming a print image of desired colors on a color image forming sheet on which a plurality of color areas are regularly formed, comprising display means for displaying a plotted image; input means for designating colors for said plotted image displayed on said display means; recording means for selectively changing colors of a desired part of said color area on said color image forming sheet; conveying means for conveying said color image forming sheet in a predetermined direction; detecting means for detecting the position of said color image forming sheet and outputting a detection signal; and control means for driving said conveying means on the basis of a detection signal from said detecting means, and driving said recording means on the basis of color designation by said input means in synchronism with the drive of said conveying means, to thereby change the color of at least a part of said color area on said color image forming sheet, thus forming a print image on said color image forming sheet with a mixture of colors of said color area.
According to a fourth aspect of the present invention, there is provided an image forming apparatus claimed in the third aspect, wherein said color area of said color image forming sheet consists of three colors of cyan, magenta and yellow, and said recording means has a plurality of recording elements which are regularly arranged correspondingly to said color area.
According to a fifth aspect of the present invention, there is provided an image forming apparatus claimed in the third aspect, wherein said color area of said color image forming sheet consists of three colors of cyan, magenta and yellow; said conveying means conveys said color image forming sheet in a direction intersecting at right angles with said stripes; and said recording means is provided with a plurality of recording elements regularly arranged in said direction of conveyance at a pitch corresponding to said pitch of stripes on said color image forming sheet, said recording means being movable in a direction intersecting at right angles with said direction of conveyance.
According to a sixth aspect of the present invention, there is provided an image forming apparatus as claimed in the fifth aspect, wherein said recording elements form dots of predetermined colors at a size corresponding to the width of said stripe, on the stripe of each color on said color image forming sheet.
According to a seventh aspect of the present invention, there is provided an image forming method for forming a print image of desired colors on a color image forming sheet by a recording means, said color image forming sheet including a plurality of color areas regulary formed, said recording means selectively changing the colors of a desired part of said color area of said color image forming sheet, said image forming method comprising the steps of producing print image data on the basis of plotted image data showing a plotted image, said print image data for forming a print image with a mixture of colors of said color areas of said color image forming sheet by changing at least a part of colors of said color areas of said color image forming sheet, controlling said recording means on the basis of said print image data to thereby form a print image on said color image forming sheet.